First let me explain the banner weight. By default all banners have the
same weight of 1. This means every banner has the same probability of
being displayed. By using the admin interface you could change the banner
weight of one or more banners to another value. For example if you change
the banner weight of banner A to 2 and the weight of banner B is 1, banner
A will be displayed twice as much as banner B. If you decide to set banner
A to a weight of 10, banner A will be displayed 10 times as much as banner
B.
By altering the weight it is possible to determine which banners will
be displayed more frequently. This way you could decide to show important
banners more frequently and provide a better service to a client and help
him create a bigger impact of his banners:
The frequency of how much a banner is displayed is directly affected by
the weight of the banner.
Banner A |
Weight 4 |
Banner B |
Weight 12 |
Banner C |
Weight 3 |
Banner D |
Weight 1 |
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The total weight of all banners is 20. It is now quite easy to determine
how many times each banner will be displayed. A banner with weight 1 will
be displayed in 1/20th = 5% of all impressions.
Banner A |
Weight 4 |
Will be displayed in 4/20th = 20% of all impressions |
Banner B |
Weight 12 |
Will be displayed in 12/20th = 60% of all impressions
|
Banner C |
Weight 3 |
Will be displayed in 3/20th = 15% of all impressions |
Banner D |
Weight 1 |
Will be displayed in 1/20th = 5% of all impressions |
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If we add the average number of impressions each day to the equation it
is very simple to determine how many impressions each add will get on
any given day.
For example: the average number of impressions each day is 20000, the
results would be:
Banner A |
Weight 4 |
20% |
4000 impressions each day |
Banner B |
Weight 12 |
60% |
12000 impressions each day |
Banner C |
Weight 3 |
15% |
3000 impressions each day |
Banner D |
Weight 1 |
5% |
1000 impressions each day |
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Of course it is impossible to predict the exact number of impressions,
due to variations in the actual number of impressions each day. Also if
you use random retrieval the banners are selected randomly. The random
number generator used is quite good, but it may not distribute impressions
evenly over a short period. There is nothing to worry about, statistically
it will be distributed evenly over a longer period.
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